Recently, with the widespread use of electronic products, display panels used in the electronic products for providing the display function have become the focus of attention by designers. There are a variety of display panels and they can be selected according to the design of electronic products. Some types of display panels do not have a light emitting function in themselves, and a backlight module is required to be disposed thereunder to provide a light source for achieving the display function.
The backlight module generally comprises an assembling frame, a light source, and a flat optical control plate. Depending on the relative positions of the light source and the flat optical control plate, the backlight module can be divided into direct type and edge type backlight modules. Taking the direct type backlight module as an example, the light source and the flat optical control plate are disposed within the assembling frame, and the light source is located below the flat optical control plate, such that light from the light source is emitted out of the backlight module after the transfer direction or distribution mode of the light is directed and adjusted by the flat optical control plate. However, although the flat optical control plate has been available for adjusting the transfer direction or distribution mode of the light in the backlight module, the mura phenomenon of some non-uniform brightness/darkness distribution still occur. Thus, how to enable the backlight module to emit light of uniform brightness is always an issue to be addressed in the art.